The Global System for Mobile Communications assembly (GSMA) is greatly promoting rich communication services (RCS). The RCS are mainly implemented by using an enhanced phone book. With the enhanced phone book, a user may directly initiate multiple communication functions, which mainly include an enhanced message and an enhanced call. The enhanced message is mainly a data-based instant message, and content of the message may be a text, a file, a video, audio, or the like. The enhanced call is mainly a data-based voice call and a data-based video call. These services are already commercialized by multiple operators in Europe, South Korea, and the like, and many operators are planning to carry out the RCS. The RCS are a next step into which operators evolve services. There are many opportunities as well as challenges. Currently, China Mobile is prepared to launch pilot commercial RCS next year. In many services, a video communication service is an important part of the RCS.
However, in the prior art, because a mechanism for negotiation between terminals that perform video communication is undesirable, terminals that have video communication capabilities cannot successfully implement video communication. As a result, efficiency and a success rate of video communication are greatly reduced, and many network resources and much electricity are consumed ineffectively. In addition, user experience of a video communication service is unsatisfactory.